The program STRKWORK calculates stroke work and stroke work index based on pressure, cardiac output (CO), R-R interval (seconds), and body surface area (BSA). The BSA is optional but is needed to calculate stroke work index.

The program SUNTIME approximates the time of sunset and sunrise based on a date in a general 365-day calendar, the person's location (longitude (east is negative, west is positive) and latitude (north is positive, south is negative)), and the time zone.

Monday, January 21, 2019

I recently received an email asking for help of how to rename columns of the Statistics Editor screen. I was not able to figure it out myself, I then asked if anyone at the Museum of HP Calculators knew.

Saturday, January 19, 2019

I
want to give a special thank you to John Cadick. Cadick requested
that I review this calculator and has loaned me his calculator to
review. Much appreciated, and John, I hope you like this review.

General
Information

Company:
Casio

Type:
Scientific – Algebraic (Perfect
Algebraic Method)

Display:
10 digits with 2 digit exponents

Power:
Solar with
battery backup (LR44)

Memory
Registers:
8: A, B, C, D, E, F, X, Y ,M

Years:
Circa
1998-1999

Original
Cost: $10
to $20, depending on the store (at the time)

Documentation:
Manual, Quick
Reference card

Two
Line Display and Fractions

The
Casio fx-85WA has a two line display: the top line for the
mathematical expression to be evaluated, and the bottom line displays
the answers. The font on the bottom line is bigger than the font on
the top line. Later models will have the fonts of both lines of
about equal size.

Screen for fx-85WAS (left) and FX-300MS (right)

You
can enter equations as they are written, no need to worry about
post-fix notation. The order of operations is effect for all
calculations.

You
can enter and do calculations with fractions with the [ a b/c ] key.
After a calculation is completed, the [ a b/c ] can convert results
between a fraction and decimal approximation. All fractions are
simplified. The maximum denominator is 9999. Conversions between
mixed fractions and improper fractions are also available.

*
Reciprocal, factorial (calculating 69! on the fx-85WS is surprising
slightly faster than later models)

*
Combination, permutation

*
Engineering notation with the [ENG] and its inverse

*
Degree-Minute-Seconds calculations [ ° ‘ “ ] and conversions

*
Fractions, random numbers, round result to the FIX settings

*
Polar and Rectangular Conversions

For
the polar and rectangular conversions, results are stored in the
following variables:

E:
x, r

F:
y, θ

Replay

The
last expression can be edited. To re-edit the last expression,
simply press either the arrow keys [ ← ] or [ → ] and edit.
Characters can be inserted and deleted.

Statistics

There
are two primary statistics modes on the fx-85WA:

*
SD (Single Deviation, 1-variable statistics)

*
REG (Regression, 2-variable statistics)

The
type of regressions are:

Lin:
Linear (y = a + b*x)

Log:
Logarithmic (y = a + b*ln x)

Exp:
Exponential (y = a + b*e^x)

Pwr:
Power (y = a*x^b)

Inv:
Inverse (y = a + b/x)

Quad:
Quadratic (y = a + b*x + c*x^2)

Data
points are entered with the [ M+ ] key with frequencies added with
the semicolon ( ; ). When data is entered, the x value is returned.
There is no data count indicator when [ M+ ] is pressed, I wish it
did. Keep this in mind.

All
the statistics registers are kept as shifted functions and alpha
registers, and they are:

SHIFT 1: mean x

SHIFT 6: sy*

RCL A: ∑x^2

RCL F: ∑xy

SHIFT 2: σx

SHIFT 7: A (intercept)

RCL B: ∑x

RCL M: ∑x^3

SHIFT 3: sx*

SHIFT 8: B (slope, x coef.)

RCL C: n

RCL X: ∑x^2y

SHIFT 4: mean y

SHIFT 9: C(x^2 coef.)

RCL D: ∑y^2

RCL Y: ∑x^4

SHIFT 5: σy

SHIFT (: r (correlation)

RCL E: ∑y

*
labeled xσn-1 and yσn-1, respectively. (sample deviation)

Keyboard

The
fx-85WA is a light calculator and pretty compact. The keys are
pretty solid, but also allow for fast typing. I like the labeling of
the keys, they are easy to read.

One
thing I am big fan of both STO (store) and RCL (recall) are primary
key functions. This is something we don’t see on scientific
calculators anymore, as often either STO or RCL is a shifted
function.

The
color of the font on the keys and labels are readable with good
contrast. The fx-85WA is a pleasure to use.

Verdict

The
fx-85WA serves a scientific calculator providing with lots of
functions. My only wish I had for this model is that top line’s
font is bigger, but that is addressed in later models.

This
model (and equivalent fx-300W) is a challenge to find. I searched
ten pawn shops and several thrift shops for this model without
success.

Before
I go: I want to thank John Cadick for lending me his calculator to
review.